1996 Dodge Dakota vacuum readings

SRTOEMVIE

MEMBER
1996 DODGE DAKOTA
6 CYL
2WD
AUTOMATIC
175,000 MILES

This questions is just about curiosity.

I connected a vacuum gauge to my engine and was just wondering if these readings are normal.

idle 500 rpm - 19in steady

2000 rpm - 22in steady

decel from quick pop - pops to zero, then back to 27in, then settles on 19in as idle becomes normal.

trans in drive, brake on - 17in steady (Why does it drop under slight load like this?)

It also drops to 17in when turning the wheel all the way one way or the other. Normal?

Is this all normal? Like I said, just curios. Especially the drop in vacuum at idle with trans in drive or rev and brake on and when turning the wheel. Thanks.

1 Reply

RACEFAN966

MECHANIC
5,029 POSTS

Ok to answer your question yes this normal. The closer to sea level you are the more vacuum an engine will produce. Now here is a way to think about it you engine is no more then a fuel burning air pump ok. It take in air which is mixed with fuel to create power and then pushed out the exhaust. Now as you step on the gas it takes in more air so the vacuum drops. Now when the idle drops IE with a load the vacuum also drops and as long as it is only a couple of points then all is ok. With the vacuum at idle being what you say it is you must be between the 2000 to 3000 elevation. The only time you sould worry about the readings is if it bounces around alot or is very low. Hope this helps.